Uefa has approved a rule to raise the quota of homegrown players in squads competing in European competition.
Clubs will be required to have four such players by 2006/2007 and this has to be upped to six the following season and eight by 2008/2009.
Half the quota should be trained by the club and the others can come from a club academy in the same country.
Meanwhile, Uefa president Lennart Johansson will step down in 2007 - a year later than planned.
The new rules will apply to clubs playing in Champions League and Uefa Cup matches.
The hope is that domestic national football associations will also implement the stipulation but that seems unlikely following the comments of the English Football Association executive director David Davies.
He said: "There are reservations in a number of countries and our view is that we have no plans to extend this domestically.
"We are not in the business of gesture politics but we will discuss this with the Professional Games Board in early May.
"Will the object of these proposals actually be achieved? Perhaps all that will happen is that some clubs will go abroad to bring in players at an even younger age."
The move was given the green light by all of Uefa's 52 member associations at a meeting in Tallinn, Estonia, on Thursday.
Uefa vice-president Per Ravn Omdal said: "This is of fundamental importance to the future of football.
"You may think that four out of 25 is a low number and it is but we want a limited and moderate step here so that the clubs can keep in line with our new rule by 2008-09."